Water is pumped up from the fish tank into the grow bed (either from the bottom of the bed if drained from the pump, or (A) above the bed). Ammonia rich waste is produced by the fish and accumulated in the water which the plants feed on.

When the siphon trips or the pump is switched off by a timer (B), water returns to the fish tank by gravity (the plants filter the waste water and contains nutrients for fishes before returning to the fish).

If you decide to customize your system by adding more grow beds, you will go from a 1:1 to a 2:1 bed to tank ratio. As a result, there will be too much water drained in every flood cycle from your fish tank unless you use an indexing valve. Low water levels could mean more stress for your fishes.

Conclusion

For a home use, a flood and drain aquaponics system design is the most suitable, especially if you’re just starting off. However, if you wish to increase your food output then you would need a more sophisticated system in place.

You would need another grow bed, add a sump tank and possibly reorganize the location of the various components in your system. If you want to learn more about this and different aquaponics system designs, I recommend that you visit here.